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policy failure puts public health at risk
policy failure puts public health at risk

By Dr. Gregory Crocetti and Georgia Miller
Friends of the Earth Australia

Design and Layout
Natalie Lowrey

September 2011

Front cover image of E. coli bacteria from
‘Times of China’

                  nano-silver: policy failure puts public health at risk

                  executive summary                                                                           2

                  introduction                                                                                4

                  bacterial resistance an emerging crisis in public health                                    7

                  the case of triclosan a cautionary lesson for nano-silver                                10

                  allergy epidemic are we too clean for our own good?                                      12

                  nano-silver still immune to regulation                                                   15

                  appendix                                                                                  18

                  references                                                                                21                                                               nano-silver: policy failure puts public health at risk   3
executive summary

Two of the greatest health problems of our                       including Professor John Turnidge, Professor Hatch Stokes
time - antibiotic resistance and the allergy                     and Associate Professor Tom Faunce, warn that the
                                                                 rapidly expanding use of nano-silver in bacteria-killing
epidemic - share a very important link.                          products could make both of these problems a lot worse.
The numbers of deaths caused by bacterial resistance to
                                                                 For nearly a century, we have waged a war on bacteria.
antimicrobials and antibiotics in hospitals continues to rise.
                                                                 We have learned to fight off these ‘enemies’ by using
Hospital-associated infections kill around 100,000 people
                                                                 stronger and stronger weapons. As the bacteria have
in the United States and 150,000 people in Europe each
                                                                 found ways to resist the lethal effects of one antimicrobial
year. More than 7,000 similar deaths occur annually in
                                                                 weapon, we have been forced to unleash another. There is
                                                                 now a real worry that we may be running out of options
At the same time, we are experiencing an epidemic in             to tackle resistant bacteria.
allergic diseases and asthma in industrialised countries.
                                                                 The medical community has been turning to nano-
Nearly 40% of children in Australia live with an allergy.
                                                                 silver as an antimicrobial of last resort. Yet at the same
In the United States, the figures are even worse – more
                                                                 time, many companies have seen a marketing advantage
than 54% of all US citizens test positive to one or more
                                                                 in including nano-silver as an ingredient in everyday
allergens; more than half US households have at least six
detectable allergens.
                                                                 Nano-silver is found internationally in toothpastes, pet
Compelling new scientific research connects these two
                                                                 shampoos, fabric softeners, bath towels, cosmetics,
serious and complex problems to the misguided ‘war on
                                                                 deodorants, baby clothes, baby bottles, refrigerators, food
bacteria’ in every aspect of our life.
                                                                 storage containers, kitchen cutting boards, underwear,
Australian health experts surveyed for this report,              ATM buttons, industrial disinfectants, agricultural pesticides

4   nano-silver: policy failure puts public health at risk
 and handrails for buses. Here in Australia, people are              to further increase the incidence of allergies.
 already coming into contact with nano-silver every day.             Research into another antimicrobial used widely in both
In interviews for this report, medical experts warn that             households and hospitals - triclosan - has revealed both
using such a powerful antimicrobial in these everyday                the mechanisms for bacterial resistance and widespread
products is not only unnecessary, but dangerous.                     incidence of triclosan-resistant bacteria in hospitals.
As with antibiotics, the overuse of nano-silver will                 Experts agree that regulators need to halt the excessive
promote resistance to this important antimicrobial.                  and unnecessary use of powerful antibacterials in
Already, there is early evidence of bacterial resistance to          everyday products. This is necessary to maintain the
silver in some clinical settings.                                    effectiveness of antimicrobials and antibiotics for clinical
What’s worse, experts interviewed for this report warn               use and to counteract the allergy epidemic.
that nano-silver will also promote resistance to antibiotics         In interviews for this report, Professors Turnidge, Stokes
and other antimicrobials.                                            and Faunce have described existing regulation (or non-
As concern grows about our allergy epidemic, scientists              regulation) of nano-silver as a policy failure.
have realised that in addition to breeding resistance in             Friends of the Earth Australia call on the government to
bacteria, our unchecked use of antimicrobial compounds               restrict the use of nano-silver in consumer, industrial and
like nano-silver might carry another hidden cost.                    environmental products.
Along with other experts surveyed for this report, Nobel
laureate Professor Peter Doherty agrees that childhood
interactions with bacteria are essential to develop strong
immune systems in children.
Widespread use of nano-silver carries the great potential

                              Reponses from expert panel to questions relating to nano-silver

                                       Prof. Hatch Stokes     Prof. John Turnidge   Dr. Diana Bowman           Assoc. Prof Tom Faunce

  Do you regard silver as an
  important antimicrobial in
  Australian hospitals – in the
                                              3                       3                    3                                    3
  context of treating serious burns?

  Are you concerned with the level
  of antibiotic resistance?
                                              3                       3                    3                                    3

  Do you agree that the
  widespread use of nano-silver in
                                              3                       3                    s                                    3
  consumer products is excessive
  and unnecessary?

  Do you agree that the regulation
  of nano-silver has been a policy
                                              3                       3                    s                                    3

  Do you think that regulators
  need to look at chemicals like
  nano-silver in terms of public
                                              3                       3                    3                                    3
  health, in addition to toxicity?                                                                               nano-silver: policy failure puts public health at risk   5

Definition of nanotechnology                                     Some commentators have suggested
Nanoparticles are commonly defined as particles with at          that there is no cause for concern
least one dimension measuring less than 100 nanometres           about silver, given that it was used
(1 nanometre = 1 billionth of a metre). Nanoparticles            as an antimicrobial in ancient Rome.
show novel physico-chemical properties compared to
                                                                 Let’s not forget that historical use
larger sized particles of the same substance.
                                                                 is no proof of safety - the ancient
Some of these new properties include:
                                                                 Romans, Greeks and Egyptians
    •     greater surface area to react with their targets
                                                                 also used lead, copper, arsenic and
    •     greater chemical and biological reactivity
                                                                 mercury in cosmetics!
    •     higher bioavailability, including uptake into
          individual cells and even cell organelles              Nano-silver is an even more effective
                                                                 antimicrobial than silver
Historical uses and properties of silver                         Nano-silver is much more efficient as an antimicrobial
Better known for its uses in photography and jewellery,          than bulk silver (Marambio-Jones and Hoek, 2010). The
it has also long been established that silver can kill           rate of ion release is generally proportional to the surface
microorganisms. The release of silver ions from different        area of a particle; nano-silver appears to be more efficient
silver compounds can cause damage to fungi, algae,               than bulk silver at generating silver ions (Wijnhoven et
bacteria and viruses, preventing their growth. This              al., 2009). In addition to this greater release of silver ions,
property has long been exploited in the use of silver            nano-silver presents new properties, including:
as an antimicrobial (Wijnhoven et al., 2009). As an               •   the ability to cross many biological barriers
antimicrobial, silver has offered the ability to disinfect
while seemingly presenting few, if any, short-term harmful        •   increased production of reactive oxygen species
effects to human beings, other than in large doses                •   capacity to deliver silver ions efficiently to the
(Luoma, 2008; Wijnhoven et al., 2009).                                surface of bacteria (Marambio-Jones and Hoek,

6       nano-silver: policy failure puts public health at risk
Nano-silver is also more readily manipulated into                                                              Most experts agree that antimicrobials
commercial products than bulk silver. Because nano-
silver can be manufactured as spheres, particles, rods,                                                        in everyday products are completely
cubes, wires, film and coatings, it can be embedded into                                                       unnecessary
a range of substrates, such as metals, ceramics, polymers,                                                     While recognising that the use of nano-silver in certain
glass and textiles (Wijnhoven et al., 2009). This has led                                                      clinical settings is of value, all experts interviewed for
to a proliferation of its use in consumer and industrail                                                       this report agreed the current widespread use of nano-
products.                                                                                                      silver in household products is excessive and unnecessary
                                                                                                               (Table 2).
Commercial use of nano-silver is                                                                               Professor Stuart Levy, Professor of Molecular Biology
                                                                                                               and Microbiology and of Medicine, and Director of the
expanding rapidly                                                                                              Center for Adaptation Genetics and Drug Resistance
The estimated worldwide market size of nano-silver was                                                         at Tufts University School of Medicine in the United
320,000 kg/yr in 2009 (Gottschalk et al., 2010), although                                                      States, suggested in 2001 that the dramatic rise in
this is expected to expand rapidly. This volume may                                                            household products containing antimicrobial agents was
appear small, however its toxicological burden might be                                                        a cause for concern. He warned that this could select
100 times, or even 10,000 times as great as this volume                                                        for resistant bacteria, alter our microflora and ultimately
of bulk silver (as per calculations in Maynard, 2006) 1.                                                       our immune systems. Levy states: “Although we need to
The Consumer Products Inventory at the Project on                                                              control pathogens when they cause disease, we do not have
Emerging Technologies lists nano-silver as the most                                                            to engage in a full-fledged ‘war’ against the microbial world”
commonly used nanomaterial in consumer products                                                                (Levy, 2001).
(PEN, 2011). Of the 1317 products listed, over 300                                                             Professor Andrew Maynard, then Chief Science Advisor
products contain nano-silver. These include toothpastes,                                                       to the Project on Emerging Nanotechnologies, cautioned
pet shampoos, water filters, fabric softeners, bath towels,                                                    in a 2008 radio interview that companies selling nano-
shoes, socks, computer keyboards, cosmetics, deodorisers,                                                      silver products were doing so without considering the
baby clothes, baby bottles, baby toys, refrigerators, food                                                     repercussions. “It’s almost as if manufacturers are like kids
containers, kitchen cutting boards, electric shavers, curling                                                  in a toy store at the moment. They’ve got new technology
irons, and much more. Manufacturers include big name                                                           nanosilver and they’re just putting it everywhere they are so
brands Crocs, Samsung, LG, Remington and Vidal Sassoon                                                         excited about it, but nobody’s really thinking about the long
(Appendix). Our brief web search for products in                                                               term consequences of that” (Living on Earth, 2008).
Australia whose manufacturers acknowledge use of nano-
silver revealed that the Consumer Products Inventory is                                                        In an interview for this report, Professor John Turnidge,
only the tip of the iceberg. Without mandatory labelling                                                       warned that: “It’s a market that created itself. In a sense,
of nano-ingredients, it is impossible for the public or                                                        that they just use fear of bacteria as a marketing tool to
regulators to quantify the true scale of commercial use of                                                     introduce products that are unnecessary” (J. Turnidge, phone
nano-silver.                                                                                                   interview 17/3/11). Professor Turnidge is Clinical Director
                                                                                                               of Microbiology and Infectious Diseases, SA Pathology,
In addition to its use in consumer products, nano-silver is
                                                                                                               Professor of Paediatrics, Pathology and Molecular and
used as an antimicrobial in a range of industrial products,
                                                                                                               Biomedical Sciences, University of Adelaide and current
including disinfectants, cleaning agents, powder coatings
                                                                                                               president of the Australian Society for Microbiology.
(coating door knobs), wall paints and air conditioning. It
has been used as a disinfectant coating throughout Hong
Kong subways (Appendix).                                                                                       Nano-silver may exert both ionic and
Early examples in agriculture may include the use of
nano-silver as a “nanobiotic” in poultry production
                                                                                                               particle-mediated toxicity
(Clement, 2009). Asian agricultural chemical companies                                                         This report focuses on the public health challenges raised
also advertise nano-silver for use as a fungicide, foliar                                                      by nano-silver, rather than its toxicity to humans or the
spray and disinfectant for fish farming (Gih Hwa, 2011).                                                       environment. Toxicity issues are discussed only briefly
                                                                                                               here. For detailed reviews on these subjects see Aitken et
Significantly, nano-silver has important applications within
a clinical setting, particularly lining wound dressings and                                                    al. (2009), Batley and McLaughlin (2010), Luoma (2008)
as coatings for medical devices, such as catheters and                                                         or Wijnhoven et al. (2009).
stents (Silver et al., 2006). Given growing resistance to                                                      Recent studies have found that nano-silver exerts both
other antimicrobials, nano-silver is used increasingly as an                                                   ion and nanoparticle-mediated toxicity. Nano-silver
antiseptic, disinfectant and for external wound treatment.                                                     delivers silver ions to exposed organisms even more
                                                                                                               effectively than bulk silver (Luoma, 2008). Nano-silver also
                                                                                                               produces reactive oxygen species (ROS) at the particle
                                                                                                               surface (Hussain et al., 2005).
                                                                                                               The toxicity of nano-silver is different to that of silver
1. Comparing a “conventional” material made up of 2 µm diameter particles, to a nanomaterial comprised of 20
nm particles, and assuming hazard is associated with either particle number or surface area, not mass.                                                                                                                          nano-silver: policy failure puts public health at risk   7
ions. Toxicity was greater in both bacteria (Luoma, 2008)        Nano-silver could increase greenhouse
and zebrafish used by regulators as a model test species
(Asharani et al., 2008). In vitro study has also shown that
                                                                 gas emissions from wastewater
nano-silver can act as a developmental neurotoxicant,            Nano-silver has been shown to impair the function of
exerting a toxicity that is distinct from that of silver ions,   bacteria in activated sludge, resulting in four times the
and related to factors including particle size, coating and      normal quantity of nitrous oxide being released (Knight,
chemical composition, in addition to ion release (Powers         2010). Nitrous oxide is 310 times more effective at
et al., 2011).                                                   trapping heat in the atmosphere when compared to
                                                                 carbon dioxide over a 100-year time period, which makes
Nano-silver can show higher bioavailability and different
                                                                 it an extremely potent greenhouse gas (UNFCCC, n.d.).
accumulation in exposed animals than silver in ionic form
(Asharani et al., 2008, Griffitt, et al., 2009). Even where
a solution of nano-silver contains a substantial number          New risks for people and environment
of aggregates and agglomerates >100 nm in size, the
                                                                 At realistic environmental exposure levels (below
bioavailability can be far higher than that of silver ions
                                                                 19 ng/L), nano-silver impaired the reproduction of
alone (Griffitt et al., 2009).
                                                                 zebrafish and cause deformities (Lee, 2007). A high-level
For more detail of ionic versus particle-mediated toxicity       international review has concluded that evidence for
please see Senjen and Illuminato (2009).                         nano-silver’s environmental toxicity is sufficient to require
                                                                 precautionary action (Aitken et al., 2009).
The loss of nano-silver from products                            The potential toxicity to humans is very poorly
                                                                 understood and inadequate to undertake human risk
into waste streams may be rapid                                  assessment (Wijnhoven et al., 2009). Nonetheless, in
Nano-silver used in some clothing can easily leak into           vitro studies have found that nano-silver was toxic to
waste water during washing. Two brands of socks lost             mammalian liver cells (Hussain et al., 2005), stem cells
nearly 100% of their silver content within four washings         (Braydich-Stolle et al., 2005) and even brain cells (Hussain
(Benn and Westerhoff, 2008).                                     et al., 2006; Powers et al., 2011).
The majority of nano-silver may be removed from                  In their review of nano-silver toxicity, Wijnhoven et al.
wastewaters and deposited in sludge or biosolids by              (2009, p25) conclude that long-term study of nano-silver’s
waste treatment (Benn and Westerhoff, 2008). Biosolids           potential toxicity to humans is required: “Developmental
could then reach the environment, as agricultural                toxicity and neurotoxicity will have dramatic consequences
fertilisers, dumping in landfills or oceans, or via              and given the equivocal carcinogenicity effects, additional
incineration (Kiser et al., 2009).                               information on these long-term endpoints is needed.”
However some anionic and uncharged nanomaterials
could pass through into sewage effluents and not be              Nano-silver could promote
retained in sewage biosolids (Batley and McLaughlin,
2010). Inevitably, the more nano-silver in incoming              mitochondria-related disease
wastewater, the more nano-silver will be lost to the             Each human cell contains ancient forms of tiny symbiotic
environment in treated effluent (Luoma, 2008). Swiss             bacteria called mitochondria – our cell’s energy
researchers recently predicted that nano-silver in sewage        producers.
treatment effluents and surface waters may already pose
                                                                 Early in vitro studies have already demonstrated that
risks to aquatic organisms (Gottschalk et al., 2009).
                                                                 exposure to nano-silver can reduce mitochondrial
                                                                 function (Hussain et al., 2005; 2006).
Toxicity to non-target bacteria                                  The number of diseases associated with mitochondrial
Microorganisms are the foundation of all ecosystems and          malfunction is ever-increasing and includes Parkinson’s,
provide key environmental services ranging from primary          Alzheimer’s and Huntington’s disease (Schapira, 2006).
productivity to nutrient cycling and waste decomposition         It appears plausible that a long-term increased exposure
(Klaine et al., 2008).                                           to nano-silver could result in increased incidence of these
                                                                 types of diseases.
Early studies have shown that nano-silver can reduce the
activities of microbes used in treating wastewater (Choi,
2008; Knight, 2010). Nano-silver contaminated effluent
released into natural waterways could also disrupt critical
bacteria-driven processes. If biosolids containing nano-
silver are applied to agricultural soil, they could reduce
soil fertility on farms.

8   nano-silver: policy failure puts public health at risk
bacterial resistance
an emerging crisis in public health

“Bacterial resistance to antibiotics is one of the biggest
challenges of the 21st century”
Professor Hatch Stokes at The ithree Institute (University of Technology Sydney) and former president of the
Australian Society for Microbiology (H.Stokes, phone interview 10/3/11)

Clinical and microbiological professionals agree that we                              Significantly, the World Health Organisation dedicated
are in serious trouble.                                                               this year’s World Health Day (April 7, 2011) ‘Antibiotic
As a result of the overuse and abuse of antibiotics, in                               resistance: No action today, no cure tomorrow’ in an effort to
recent decades antibiotic resistance has increased in                                 raise awareness about this problem.
bacterial pathogens. This has led to treatment failures in
both human and animal infectious diseases (WHO, 2007).                                Nano-silver’s role in hospitals
Professor Peter Collignon, Director of Infectious Diseases
and Microbiology at the Canberra Hospital and Australian                              The rapid rise in antibiotic resistance has required the
                                                                                      increased usage of other antimicrobials in disinfectants
National University Medical School, warned recently:
                                                                                      and antiseptics within clinical settings. These include
“We’ve got resistant bacteria causing infections in people
                                                                                      hypochlorites, quaternary ammonium compounds, nano-
that are either untreatable or close to being untreatable”
                                                                                      silver and triclosan. Nano-silver is also used in wound
(AAP, 2011).
                                                                                      dressings, especially for burns, and to control bacteria on
In the United States (US), 1 in 17 hospital infections kill.                          catheters and stents.
The US Center for Disease Control and Prevention                                      There is widespread - albeit not universal - recognition of
estimates that each year, roughly 1.7 million hospital-                               the clinical utility of silver wound dressings (Salleh, 2010).
associated infections, from all types of bacteria combined,                           Professor Roy Kimble of the University of Queensland
cause or contribute to 99,000 deaths. In Europe, hospital-                            and director of burns and trauma at the Royal Childrens
associated infections are thought to cause or contribute                              Hospital in Brisbane has observed that, “The vast majority
to 147,000 deaths each year (WHO, 2010). In Australia,                                of burns surgeons in Australia use silver dressings” (Salleh,
the 7,000 deaths annually from hospital-associated                                    2010). Professor Collignon has previously advised that
infections is four times greater than our road toll.                                  nano-silver is very useful in stopping the growth of                                                                                                nano-silver: policy failure puts public health at risk   9
bacteria on medical devices without relying on antibiotics                                              bacteria present (Chopra, 2007).
(Salleh, 2009).                                                                                         It therefore appears likely that widespread household
However concern exists that nano-silver could adversely                                                 use of products that release lower levels of silver ions,
affect patient host cells. This could delay wound healing                                               for example dish cloths, baby mattresses, toothbrushes
or pose localised toxicity (Luoma, 2008). This, in addition                                             or computer keyboards, may be especially problematic
to concerns about promoting bacterial resistance (see                                                   breeding grounds for bacterial resistance.
below), suggests that clinical use of nano-silver should be
                                                                                                        In 2008, Professor Andrew Maynard warned explicitly
limited to patients and anti-microbial applications of most
                                                                                                        that widespread consumer and industrial use of nano-
value, where alternative disinfectants are not effective.
The potential for nano-silver’s widespread clinical use (for                                            silver could compromise its medical role: “At the moment
example, in cleaning products, soaps and sheets) to drive                                               silver is one of our last defenses against some of these bugs
more rapid develop of bacterial resistance to nano-silver                                               these microbes that are resistant to many other forms of
also suggests a need for restrained use.                                                                antimicrobial agents. If we give the secret of our last best
                                                                                                        defense away, silver, it leaves us with very little else to kill
Assoc. Prof. Faunce suggests that hospital and health care                                              these harmful agents… It literally is the silver bullet and I
providers should establish guidelines to restrict clinical
                                                                                                        think we have to use it judiciously” (Living on Earth, 2008).
use of nano-silver for critical applications and patients (T.
Faunce, phone interview 15/3/11).                                                                       In interviews for this report, other experts agree.
                                                                                                        Professor Stokes warns “the use of antimicrobials outside
                                                                                                        of the clinical context indirectly facilitates and further raises
What doesn’t kill bacteria makes                                                                        the possibility that such resistance genes are going to make
them stronger                                                                                           their way into very serious pathogens, and at that point , it
                                                                                                        becomes a major health problem….and if we start using
                                                                                                        nano-silver quite broadly in the environment, then not only
                                                                                                        will we have bacteria that are resistant to nano-silver, then
                                                                                                        I would bet that they’ll already be multi-drug [antibiotic]
                                                                                                        resistant as well” (H. Stokes, phone interview 10/3/11).
                                                                                                        Professor Turnidge suggests that “prudence and restraint
                                                                                                        are probably the critical factors largely missing from what we
                                                                                                        do. We use [antimicrobials] much, much more than we need
                                                                                                        to as a society” (J. Turnidge, phone interview 17/3/11).

                                                                                                        Early evidence of nano-silver resistance
                                                                                                        has already emerged
                                                                                                        It is difficult to know how widespread bacterial resistance
                                                                                                        to silver might already be in our hospitals and broader
                                                                                                        society (Chopra, 2007). Nonetheless, there are already
                                                                                                        several reports describing its emergence. As cited by
                                                                                                        Gupta (2001) “The first report on the genetic and
                                                                                                        molecular basis for Ag+ [ionic silver] resistance concerned
                                                                                                        a Salmonella typhimurium isolate, from the Massachusetts
                                                                                                        General Hospital, that killed several patients and required
                                                                                                        the closing of the burn ward in 1975 (McHugh et al.,
                                                                                                        Silver-resistant bacteria have been repeatedly found in
                                                                                                        hospital burn wards (examples listed by Chopra, 2007),
                                                                                                        where the silver compound silver-sulfadiazine has been
Figure 1: Selection of bacterial resistance to antimicrobials, based on diagram by GreenFacts (2009).
                                                                                                        used for decades to treat burns patients. In particular, a
                                                                                                        2003 investigation in a Chicago hospital found more than
                                                                                                        10% of clinical isolates had silver resistance genes (Silver,
Widespread use of nano-silver outside                                                                   2003). A relatively recent study also reported strains
clinical settings may promote rapid                                                                     of bacteria able to survive high concentrations of silver
                                                                                                        nanoparticles (Lok et al., 2007).
development of resistance
Experts recognise that to minimise development of
resistant bacteria in clinical settings, wound dressings must
release high levels of silver ions, in an attempt to kill all

10         nano-silver: policy failure puts public health at risk
Exposure to silver can promote
resistance to many other antimicrobial
compounds as well
Selection of bacteria with the ability to resist silver
also selects for other antimicrobial resistance genes.
Genes conferring antimicrobial resistance regularly
travel quickly and widely due to the presence of
mobile genetic (DNA) elements, such as plasmids,
viruses, transposons and integrons. Resistance genes
to silver have been found on a range of plasmids,
notorious for containing multiple antibiotic resistance
genes (Gupta et al., 2001; Silver, 2003).
Professor Stokes warns that the risk we face is not
just silver resistance, adding “the one thing that I’d
put money on is that silver resistance is very closely
linked in a genetic sense to other types of antimicrobial
compounds, like antibiotic resistance’s kind-of
like a double whammy” (H. Stokes, phone interview
10/3/11).                                              nano-silver: policy failure puts public health at risk   11
the case of triclosan
a cautionary lesson for nano-silver

“The usage of nano-silver is equally                                           is a non-specific antimicrobial - it has the ability to kill
                                                                               good microbes as well as the bad (Saleh et al., 2010). Also,
as frustrating, bizarre and stupid
                                                                               similar to nano-silver, triclosan has demonstrated toxicity
as the use of triclosan in consumer                                            to a range of higher life forms such as aquatic algae
products, which is very widespread                                             (Tatarazako et al., 2004) and has been shown to interfere
now. Antiseptics in toothpaste, washing                                        with nitrogen cycles in soil (Waller and Kookana, 2009).
powder, god knows what else. It’s a
market that created itself. In a sense,                                        Widespread triclosan use has driven
that they just use fear of bacteria as a                                       bacterial resistance to both it and other
marketing tool to introduce products                                           clinically useful antibiotics
that are unnecessary. And nano-silver
                                                                               The use of antimicrobials like triclosan selects for bacteria
in consumer products is equally loony.”                                        with genes resistant to antibiotics. Several studies have
Professor John Turnidge, Clinical Director of Microbiology and Infectious      demonstrated the prevalence of triclosan resistant
Diseases, SA Pathology,Professor of Paediatrics, Pathology and Molecular       bacteria (Yazdankhah et al., 2006; Bailey et al., 2009; Chen
and Biomedical Sciences, University of Adelaide and current president of the
Australian Society for Microbiology (J.Turnidge, phone interview 17/3/11).     et al., 2009). Clinical surveys have also found widespread
                                                                               triclosan resistant bacteria that are also resistant to
                                                                               clinically important antibiotics. This has led scientists to
Triclosan offers a cautionary experience for nano-                             caution against the indiscriminate use of triclosan (Mima
silver. Just like nano-silver, triclosan is another major                      et al., 2007; Chen et al., 2009).
antimicrobial agent now widely found in both consumer
products and clinical settings. This has led to high
resistance levels, compromising its clinical use and posing                    Triclosan disrupts the development of
new public health threats.
                                                                               the immune system
                                                                               Researchers have found that people age 18 and under
The history of triclosan                                                       with higher levels of triclosan in their urine were
The compound triclosan (2,4,4’-trichloro-2’-                                   significantly more likely to report diagnosis of allergies
hydroxydiphenyl ether) was first developed and                                 and hay fever (Clayton et al., 2011). This research used
introduced as an antimicrobial and preservative in the                         data from thousands of individuals from the US National
1960s. Since this time, triclosan has been used in clinical                    Health and Nutrition Examination Survey. This is the first
settings as an antiseptic, but also within a vast range of                     time that exposure to an antimicrobial has been strongly
domestic products, including hand soaps, toothpastes,                          linked to alteration of the development of the human
mouthwash, deodorants, cutting boards, wound                                   immune system.
disinfectants, facial tissues, plastic utensils, socks and toys
(Yazdankhah, et al., 2006). And, like nano-silver, triclosan

12      nano-silver: policy failure puts public health at risk
Governments agree that triclosan has                           The failure of regulators to restrict the use of triclosan
                                                               is striking in light of their explicit recognition of the
serious potential to harm, but say there                       problems triclosan has brought.
is insufficient evidence to regulate
Regulatory bodies in the United States, Europe and
Australia have all conducted recent reviews into triclosan,
focussing on different aspects of its toxicity and potential
for bacterial resistance (USEPA, 2008; NICNAS, 2009;           Reason demands we act now
SCCS, 2010). All reviews warn of the environmental
                                                               There are many similarities between triclosan and nano-
toxicity hazard, as well as risks involved in human handling
                                                               silver. The weight of laboratory evidence and expert
and over-exposure to this chemical. Nonetheless, they
                                                               opinion suggests that the widespread use of these
all effectively concluded that there was not enough
                                                               antimicrobials could increase bacterial resistance to
scientific evidence to restrict the widespread use of this
                                                               multiple antimicrobials within pathogenic bacteria, whilst
compound. The one exception has been a ruling by the
                                                               eradicating the beneficial bacteria around us. We may
European Union to restrict the contact of triclosan with
                                                               never gather enough causal data to comprehensively
food (SCCP, 2006). Even in Europe, which prides itself
                                                               identify and quantify these public health risks. We should
on precaution-based chemicals regulation, a lack of full
                                                               instead apply precaution to restrict the widespread use of
scientific certainty (and the complexity of conducting
                                                               these powerful antimicrobials.
non-laboratory based experiments that demonstrate
causality) is being used as the reason to indefinitely delay
regulation.                                                                       nano-silver: policy failure puts public health at risk   13
allergy epidemic
are we too clean for our own good?
“There’s been an epidemic increase in                                          With most wars children are often the first to bear the
                                                                               consequences and the war on bacteria is no exception.
allergic diseases - such as asthma, food                                       Allergies and asthma have rapidly become a major public
allergies, dermatitis - over the last 40                                       health problem in industrialised countries.
or 50 years, such that now in Australia                                        Scientists have looked to explain this rapid increase
as many as 40% of children will have an                                        in allergies in terms of inheritable genes or industrial
allergy to something and many of those                                         pollutants, but have ruled these out (Table 1). It now
will go on to develop diseases.”                                               appears that our use of antimicrobial compounds like
                                                                               nano-silver might carry a hidden price.
Winthrop Professor Susan Prescott, from University of Western Australia’s
School of Paediatrics and Child Heath (ABC Stateline, 2004).

                                                                               What is causing this epidemic?
“… putting yet another consumer                                                The ‘hygiene hypothesis’ was first proposed in 1989
                                                                               to explain the rapidly increased incidence of hayfever
product out to kill ‘germs’ is exactly
                                                                               in England (Strachan, 1989). This idea suggested that
the wrong thing. Germs are good for                                            decreased exposure to infectious agents early in life
you. We actually need to promote the                                           (owing to increased use of antibiotics, vaccination and
message that the immunologists are                                             sanitation) results in unbalanced immune responses to
now putting out – that almost all germs                                        antigens later in life, causing allergies. More recently, this
                                                                               hypothesis has been modified to the ‘microflora hypothesis’
are good for you. The more good germs                                          (Noverr and Huffnagle, 2005) or ‘old friends’ hypothesis
you get exposed to the less bad germs                                          (Rook and Brunet, 2005).
and allergies you will have.”                                                  These new names shift the focus to the need for humans
Professor John Turnidge, Clinical Director of Microbiology and Infectious      to be exposed to environmental microbes like bacteria
Diseases, SA Pathology,Professor of Paediatrics, Pathology and Molecular       and fungi during our childhood to help prime our
and Biomedical Sciences, University of Adelaide and current president of the
Australian Society for Microbiology (J.Turnidge, phone interview 17/3/11).
                                                                               immune systems. Too little exposure to these microbes
                                                                               prevents the development of a well-balanced immune
                                                                               system, leading to a range of potential diseases, allergies
                                                                               and disorders later in life.

14      nano-silver: policy failure puts public health at risk
The double-edged sword of disease
The rise of modern sanitation and antibiotics has
led to the dramatic decrease in infectious diseases
(such as pneumonia and diarrhoea) as well as
other positive health indicators like lowered infant
mortality. However, autoimmune diseases and
allergies that were virtually unknown to medicine
before the 20th century have now become
Humans have co-evolved with a wide range of
microbes, both ‘good’ and ‘bad’ (pathogenic). There is
a growing body of compelling evidence that suggests
that many of these microbes - both on us and inside
us - play an important role in the development
of our immune system and in protecting us from
immune-related diseases (Mazmanian and Kasper,

Exposure to microbes strengthens
childhood immune systems
The occurrence of allergies and immune diseases
like asthma in industrialised countries continues to
rise. Interestingly, not all children are equally at risk.
A 2007 Canadian survey of over 13,000 children
found that children who grow up on farms have
less than half of the risk of developing asthma than
other rural children and children in cities (Midodzi
et al., 2007). A similar trend was found in European
children, where a greater diversity of microbes
present in children’s home environments was
significantly linked with a lowered risk of asthma
(Ege et al., 2011).
In a recent interview Professor Peter Sly from the
Queensland Children’s Medical Research Institute
agreed with these findings (ABC, 2011):
“Exposure to bacterial products, particularly from
animals and farming-related activities, helps educate
the immune system as to what to ignore in the
environment and that helps to protect [against] the
development of allergies and asthma, whereas in the
city, kids don’t get quite the same sort of bacterial
exposures” he said.
Other comparative studies into autoimmune and
allergic diseases add further support to the idea that
we, in the industrialised world, have become too
clean (Table 1).
Nobel laureate Professor Peter Doherty agrees that
childhood interactions seem to benefit our immune
system and adds “Kids need to play in the dirt, and on
the floor” (Pers Comm 24/03/11).                                              nano-silver: policy failure puts public health at risk   15
                                                                      Friendly bacteria have a key role in health
                                                                      Recent research suggests that many skin bacteria are not just
                                                                      harmless – they are actually beneficial to our health (Lai et al., 2009;
                                                                      Cogen et al., 2010). Even before we are born, maternal exposure
                                                                      to microbes appears critical for protecting offspring from asthma
                                                                      (Conrad et al., 2009).

                                                                      Deploying nano-silver in the every day ‘war on
                                                                      bacteria’ could prove a great mistake
                                                                      Nano-silver is an unselective antimicrobial - it efficiently kills both
                                                                      good and bad microbes. Widespread use in consumer products
                                                                      means routinely placing this potent antimicrobial in close contact
                                                                      with our bodies. In addition to promoting microbial resistance,
                                                                      this will reduce our body’s exposure to good bacteria, potentially
                                                                      compromising our immune system and increasing the chance of
                                                                      contracting immune diseases and allergies.

Table 1. A comparison of the research looking at the incidence of autoimmune and allergic diseases with human
lifestyles. This table demonstrates that the increasing trend towards these diseases cannot easily be linked to industrial
pollutants or genetics. It also suggests a protective role in the sharing of microflora between children.

                    Findings                                               Implications                                     Study

 Children who grow up on farms are much                        Dismisses the role of urban industrial       Midodzi et al., 2007
 less likely to have asthma as other non-                      pollutants in allergies                      Ege et al., 2011
 farming rural and city children                               Strongly suggests a protective role in
                                                               exposure to diverse microbes
 Upon the fall of the Berlin Wall, rates of                    Dismisses the role of urban industrial       Von Mutius et al., 1994
 asthma were higher in West Germany                            pollutants in allergies
 than in East Germany - even though air
 pollution was worst in the East

 Having one or more older siblings                             Strongly suggests a protective role in the   Strachan, 1989; Ponsonby et al., 2005;
 significantly lowers the incidence of hay                     sharing of microbes                          Cardwell et al., 2008
 fever, asthma, Type I diabetes and multiple

 Child care during first 6 months lower                        Strongly suggests a protective role in       Ball et al., 2000
 incidence of asthma and eczema                                exposure to diverse microbes

 Auto-immune diseases are rare in rural                        Dismisses the role of genetics in the        Detels et al., 1972; Symmons, 1995
 Asia and Africa, but rise sharply when                        inheritance of allergies
 immigrants from those countries come to
 the developed world

 Type I diabetes is 6 times more prevalent                     Dismisses the role of genetics in the        Kondrashova et al., 2005
 in Finland as in neighbouring Russia, in                      inheritance of allergies
 spite of similar genetic backgrounds

16    nano-silver: policy failure puts public health at risk
     nano silver
     still immune to regulation

Truck-sized gaps leave nano-silver                             Biocidal Silver – Extreme Germ Killers Present a Growing
                                                               Threat to Public Health (Senjen and Illuminato 2009),
effectively unregulated                                        prominent microbiologists, including Professors Hatch
As with the EU and US systems, Australian regulations are      Stokes and Peter Collignon, warned that the widespread
primarily focused on “new” chemicals. To date, Australian      use of nano-silver could drive antimicrobial resistance.
legislation fails to recognise that nanoparticles present      Since that time no action has been taken by relevant
new and often greater toxicity risks than larger (bulk)        regulatory bodies or the Australian government to halt its
particles of the same composition (Bowman and Hodge,           widespread use.
2006). This leaves nano-silver effectively unregulated, with
no requirements for companies to conduct and submit
risk assessments before use.
                                                               Experts warn nano-silver is a policy
In an interview for this report, Dr. Diana Bowman, Senior      failure
Research Fellow in the Melbourne School of Population          Most Australian experts interviewed for this report -
Health at The University of Melbourne, emphasised              Professors Turnidge, Stokes and Faunce - agreed that the
that nanoparticles not triggering assessment was a             absence of effective nano-silver regulation amounts to a
key regulatory gap. However even if this trigger were          policy failure.
activated, there is still no requirement or mandate for        When asked if he was disappointed in the government’s
regulators to assess public health. Dr. Bowman agreed          response to experts’ calls to regulate nano-silver to
that the narrow remit of regulators to assess broader          prevent antimicrobial resistance, Professor Turnidge
implications was a key barrier to effective regulation of      responded: “Yes, but it’s in keeping with the whole antibiotic
 nano-silver (D. Bowman, interview 11/3/11).                   resistance story. Recent meetings have highlighted that a
Following the release of the 2009 FoE report, Nano &           decade of cage rattling has had virtually no positive effect.                                                                        nano-silver: policy failure puts public health at risk   17
When asked, the government put up a few phantoms and               Australian regulators to take on world’s best practice – and
say “we’re doing this and we’re doing that - but they’re not       that they try to understand the precautionary principle.
doing anything. It’s classic bureaucratic whitewash, sadly” (J.    There are enough studies out there that show that there is a
Turnidge, phone interview 17/3/11).                                distinct effect of nano-silver at small sizes. In that sense, the
                                                                   product nano-silver needs to be regulated in its own right and
                                                                   not simply regarded as another version of silver” (T. Faunce,
Lip service to the precautionary                                   phone interview 15/3/11).
principle – but no precaution in practice
The Australian Government was a signatory to the most
widely accepted version of the Precautionary Principle -
the Rio Declaration on Environment and Development
(UNEP, 1992), which states:
“In order to protect the environment, the precautionary
approach shall be widely applied by States according to their
capabilities. Where there are threats of serious or irreversible
damage, lack of full scientific certainty shall not be used as
a reason for postponing cost- effective measures to prevent
environmental degradation”.
A precautionary approach to managing nanotechnology
risks has been advocated by high level groups elsewhere.
The German Federal Institute for Risk Assessment
(BfR) has twice considered aspects of nano-silver
toxicity and bacterial resistance. It concluded that a
reliable assessment of health risks was not yet possible,
recommending that manufacturers avoid the use of
nano-silver compounds in food and everyday products
until the data are comprehensive enough to allow for a
conclusive risk assessment to ensure products are safe
for consumer health (BfR, 2009; BfR, 2011).
 Similarly, in the United Kingdom, the Royal Society and
 Royal Academy of Engineering have recommended
 that nanoparticles should be regulated and assessed as
 new chemicals and face mandatory labelling due to the
 seriousness of nanotoxicity risks (UK RS/RAE, 2004).
 On 11 July 2008 Senator Kim Carr, the Minister for                                               Illustration by Maude Farrugia
 Innovation, Industry, Science and Research, released the
 Australian Government Objectives for the Responsible
 Management and Oversight of Nanotechnology.
                                                                   Australia’s nanotechnology business
 This document claimed the Australian Government                   friendly regulatory environment
 will “Protect the health and safety of humans and the             In stark contrast to the precautionary principle, a recent
 environment”, by continuing to “apply a precautionary             Australian Government nanotechnology report touts
 approach consistent with Australia’s international                praise by the OECD for our lax regulation (DIISR 2011,8):
  obligations, including the Rio declaration” (DIISR, 2008).
                                                                   “In 2006, the OECD cited Australia’s approach to regulation
 The Australian Government Department of Health and                as a best practice benchmark for other OECD countries.
 Ageing has also recognised the precautionary principle            Australia was identified as having the fewest restrictions on
 as being “particularly relevant” within the context of            product markets of the 30 OECD countries, the least public
 administrative policy (DHA, 2001).                                ownership of business and the least restrictive impact of
 However, in spite of these commitments, the                       business regulation on economic behaviour. Australia has
 management of nanotechnology in Australia has                     been ranked as the third fastest place in the world to start a
 been anything but precautionary. Nano-silver                      business”.
 remains effectively unregulated; the Royal Society’s
                                                                   Assoc. Prof. Faunce suggests that “For some reason,
 recommendations have been ignored.
                                                                   Australian regulators seem to be more sympathetic to
  Assoc. Prof. Faunce, Australian Research Council Future          industry wanting to use these particles – more than the
  Fellow at the Australian National University, suggests           environment. There seems to be a sort of inertia to take into
  that regulators should take control of nano-silver               account the environmental and health hazards of nano-
  seriously and act strongly “all we’re really asking is for       silver” (T. Faunce, phone interview 15/3/11).

18    nano-silver: policy failure puts public health at risk
Table 2. Reponses from expert panel to questions relating to nano-silver during interviews between March 10-17, 2011.

                                       Prof. Hatch            Prof. John            Dr. Diana                        Assoc. Prof
                                         Stokes               Turnidge              Bowman                           Tom Faunce

 Do you regard silver as an
 important antimicrobial in
 Australian hospitals – in the
                                            3                      3                     3                                     3
 context of treating serious burns?

 Are you concerned with the level
 of antibiotic resistance?
                                            3                      3                     3                                     3

 Do you agree that the
 widespread use of nano-silver in
                                            3                      3                     s                                     3
 consumer products is excessive
 and unnecessary?

 Do you agree that the regulation
 of nano-silver has been a policy
                                            3                      3                     s                                     3

 Do you think that regulators
 need to look at chemicals like
 nano-silver in terms of public
                                            3                      3                     3                                     3
 health, in addition to toxicity?

Experts agree that we cannot consider                             there is a pressing need to act to manage the public health
                                                                  threats from the widespread use of nano-silver (Table 2).
the risks of nano-silver based solely on                          This is a key challenge for the regulatory body National
laboratory-based toxicology, but must                             Industrial Chemicals and Assessment Scheme (NICNAS),
also assess broader implications for public                       as it considers new regulations to control nano-silver and
                                                                  other nano-forms of existing chemicals.
 Professor Stokes expressed his surprise as to why the
government was not more concerned to curtail the                       Conclusion
widespread use of nano-silver given the cost implications of           The widespread use of nano-silver carries a great
antibacterial and antibiotic resistance: “The cost of managing         potential to cause harm. Based on current trends,
antibiotic resistance in hospitals is enormous...I would have          it is reasonable to suspect that widespread use of
thought from a government perspective that they would be               nano-silver will contribute to:
looking at the problem, if only from self-interest” (H. Stokes,
                                                                       • greater numbers of deaths related to
phone interview 10/3/11).
                                                                         antimicrobial resistant bacteria in hospitals
Dr. Bowman believes that there is definitely a need to look
                                                                       • an increase in immune-related diseases and
beyond the laboratory when considering risk, however
                                                                         conditions in the community, and
recognises that the scope of the legislative remit restricts
how broadly regulators can assess the risk of nano-silver.             • further damage to the wider environment
“It is not surprising that one of the things we have found when        Friends of the Earth calls on the Ministers for
talking to regulators is that there may have been things we’d          Innovation and Health, Kim Carr, Catherine King
like them to look at, but their hands are tied”                        and Nicola Roxon to act to ensure that Australian
(D. Bowman, interview 11/3/11).                                        regulators have the power to limit the widespread
All Australian experts interviewed for this report agree               use of nano-silver.                                                                            nano-silver: policy failure puts public health at risk   19
Examples of nano-silver products available online or within Australia

             Product                                      Manufacturer      Nano-silver claim                              Website

Soap                                             COR                     “The particles of Cor soap’s 
                                                                         active ingredients, including silver,  cor-silver-soap-30g-p-5907.aspx
                                                                         sericin, collagen and chitosan,
                                                                         are dramatically reduced in size,
                                                                         reaching deep below the surface,
                                                                         killing bacteria, minimizing wrinkles,
                                                                         moisturizing and feeding vital
                                                                         nutrients to the skin”.

Baby bottle                                      GoBiz                   “Feeding bottles and mug cups           http://www.gobizkorea.
                                                                         developed with this technology,         com/blog/ProductView.
                                                                         help protect babies with weak           do?blogid=dream21&id=860332
                                                                         immunity from ge[r]ms, the
                                                                         source of all diseases. Through
                                                                         new Nano-poly technology
                                                                         [1/1000,000,000m], and cutting-
                                                                         edge science, for the first time in
                                                                         the world, this perfectly prevents
                                                                         Secondary Virus Inflammation by
                                                                         controling germs, and acting as
                                                                         an anti-bacterial deodorant, and
                                                                         maintaining freshness up to 99.9%
                                                                         without additional disinfecting by
                                                                         boiling and sterilization”.

Baby toothbrush                                  GenEzentials            “This toothbrush is made of   
                                                                         safe and clean non-toxic silicon,       genezentials-products/baby-silicon-
                                                                         contains silver nano (Ag+), and         finger-toothbrush/silicon-finger-
                                                                         the negative ions released from         toothbrush
                                                                         the bristle inhibit bacteria, viruses
                                                                         and fungi”.

Ladies Cycling Jersey                            Scody                   “Silpure is a state-of-the-art
                                                                         antimicrobial. Silpure® utilizes the au/ecom/rebel/product_detail.
                                                                         natural ability of silver to limit the aspx?id=32697&cat=2410
                                                                         growth of odor-causing bacteria
                                                                         and represents a new generation
                                                                         antibacterial technology for topical
                                                                         application to textiles. “

20     nano-silver: policy failure puts public health at risk
              Product            Manufacturer       Nano-silver claim                                   Website

Cleaning cloth           E-CLOTH                 “The cloth incorporates natural
                                                 nano-silver to kill bacteria caught  product/E-Cloth-Antibacterial-
                                                 in the cloth. Further tests showed Cloth.html
                                                 that, after a rinse with warm water,
                                                 E-cloths re-introduced just 0.01%
                                                 of bacteria back onto a sterile

Socks                    AgActive                “Through a process of Nanometer
                                                 Technique, our clothing destroys     au/
                                                 many of the bacteria, fungi and
                                                 viruses that cause infection, odour,
                                                 itchiness and sores”.

Shoes                    Crocs                   “Croslite Ag+™ material expands
                                                 upon the comfort attributes              html
                                                 inherent to Croslite™ material 
                                                 while adding anti-bacterial, anti-       releases/top-us-government-
                                                 fungal and odor resistant nano-          agency-validates-benefits-of-
                                                 Silver ceramic crystals”.                croslite%E2%84%A2-material/

Sports jacket            ASAT                    “Nano Silver technology kills  
                                                 bacteria to virtually eliminate          au/p/ASEBLZ3XL/ASAT+Elite+Ex
                                                 human odour. Anti-microbial              treme+Layer+Zip+Mock.html
                                                 formula requires no special
                                                 activation and will not wash away
                                                 in the laundry”.

Food storage container   Prepology Kitchenware   “Each container in this nine-  
                                                 piece set features silver nano           aspx/view.2/app.detail/params.
                                                 technology that's embedded in            item.K30602.desc.Prepology-
                                                 the polypropylene lid. This helps to     9piece-Nano-Silver-Food-Storage-
                                                 slow down the introduction and           Set?&cookie=set
                                                 buildup of bacteria”.

Food storage container   Kinetic                 “Approved Nano Silver          
                                                 Technology that keeps your foods         product.asp?cat=59&subcat=113
                                                 fresher up to 3 times longer than
                                                 conventional plastic food storage”.

Bed mattress             Therapedic              “The border fabric contains "Silver
                                                 Nano Technology" – Traces of real        Therapedic-pg10573.html
                                                 silver, known for its anti-microbial     http://www.snuggle-inaustralia.
                                                 and anti-static properties”.   

Refrigerator             Samsung                 “Silver Nano particles coated on
                                                 the inner walls of the refrigerator      consumer/home-appliances/
                                                 stop bacteria from multiplying,          refrigerator/side-by-side/
                                                 helping keep the inside of the           RS23HDURS1/XSA/index.
                                                 refrigerator clean and hygienic”.        idx?pagetype=prd_detail

Vacuum cleaner           LG                      “The hygienic Nano-Silver      
                                                 technology minimises the growth          download/Vacuum_Range_
                                                 of bacteria in the dust container        Brochure.pdf
                                                 for a healthier environment”.                                                                nano-silver: policy failure puts public health at risk   21
             Product                                     Manufacturer      Nano-silver claim                            Website

Epilator                                        Remington               “Depilation head with Nano            http://www.drugstore.
                                                                        Silver which inhibits the growth of   com/products/prod.
                                                                        micro-organisms on the head”.         asp?pid=210106&catid=45531

Hair brush                                      Lady Jayne              “The Lady Jayne Salon Professional
                                                                        range has a unique gel grip handle hair/hair-accessories/16137-brush-
                                                                        for comfortable styling, ionic        ceramic-radial
                                                                        technology for strong, smooth hair
                                                                        and nano silver for its antibacterial

Hair straightener                               Vidal Sassoon           “Nano silver – combines micro
                                                                        particles of ceramic and silver       Products/straighteners/VS2085A/
                                                                        (antibacterial element) for           pdf/mf1596.pdf
                                                                        enhanced shine and healthy
                                                                        looking hair”

Pool cleaner                                    Zodiac                  “Silver Nano Technology for 
                                                                        ultimate bacteria fighting            products/mineral-purification-
                                                                        capabilities”.                        systems/n2-express-mineral-

Paints and surface coatings                     Bioni Hygienic          “Silver Nanoparticles in wall paint
                                                                        prevent the formation of mould        au/Press%20Release/Paint%20
                                                                        inside buildings and the growth of    technology%20from%20
                                                                        algae on outside walls”.              Nanovations.pdf

Industrial disinfectant for Hong                MTR                     “99.9% effective in killing a wide
Kong trains and subway                                                  range of viruses and bacteria         corporate/file_rep/PR-06-084-E.
                                                                        under a laboratory-controlled         pdf
                                                                        environment. The coating lasts for
                                                                        about three years after application
                                                                        and MTR will conduct checks
                                                                        every eight months to ensure the
                                                                        bacteria-fighting powers remain

Agricultural fungicide                          NSM                     “Strong anti-fungal properties
                                                                        have found extensive usage in the     ecs.asp
                                                                        agriculture sectors to improve
                                                                        germination and to accelerate
                                                                        growth and development without
                                                                        the use of chemical”.

Aquaculture disinfectant                        Gih Hwa Enterprise      “Eliminate the diseases caused
                                                                        by bacteria, virus and fungi,         silver.html
                                                                        such as Aeromonas hydrophila,
                                                                        Edwardsiellosis, Red spot disease,
                                                                        mold, and Streptococcus”

22    nano-silver: policy failure puts public health at risk
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24       nano-silver: policy failure puts public health at risk
 “The concern for me is that the widespread use of nanosilver in consumer products like socks,
children’s toys [and] keyboards has the potential to promote resistance within bacteria – so the
                      powerful usage in the medical setting will be ruined.”
                                     Dr. Diana Bowman, Senior Research Fellow,
                         Melbourne School of Population Health at The University of Melbourne

   “If we start using nano-silver quite broadly in the environment, then not only will we have
  bacteria that are resistant to nano-silver, then I would bet that they’ll already be multi-drug
                                  [antibiotic] resistant as well.”
                     Professor Hatch Stokes, The ithree Institute (University of Technology Sydney)
                            and former president of the Australian Society for Microbiology

 “For some reason, Australian regulators seem to be more sympathetic to industry wanting to
 use these particles – more than the environment.There seems to be a sort of inertia to take
                into account environmental and health hazards of nano-silver.”
                                          Associate Professor Thomas Faunce
                     Australian Research Council Future Fellow at the Australian National University

“The usage of nano-silver is equally as frustrating, bizarre and stupid as the use of triclosan in
 consumer products, which is very widespread now. Antiseptics in toothpaste, washing powder,
  god knows what else. It’s a market that created itself. In a sense, that they just use fear of
  bacteria as a marketing tool to introduce products that are unnecessary. And nano-silver in
                             consumer products is equally loony.”
                    Professor John Turnidge, Clinical Director of Microbiology and Infectious Diseases,
                 SA Pathology, Professor of Paediatrics, Pathology and Molecular and Biomedical Sciences,
                  University of Adelaide and current president of the Australian Society for Microbiology

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